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Scientists have discovered tiny fossils that are thinner than a human hair and are an astounding 3.7 billion years old, making them the oldest known fossils on Earth, University College London announced on Wednesday. They could even be as old as 4.2 billion years.

The fossils were likely created by bacteria that lived near hydrothermal vents and consumed iron. Those ancient critters lived an incredible 3.8 to 4.3 billion years ago.

“Our discovery supports the idea that life emerged from hot, seafloor vents shortly after planet Earth formed,” Matthew Dodd, a PhD student at the University College London and the first author of a new study about the fossils, said in a statement. “This speedy appearance of life on Earth fits with other evidence of recently discovered 3,700 million year old sedimentary mounds that were shaped by microorganisms.”

The scientists found the fossils in a part of Quebec, Canada, known for having ancient sedimentary rock. The little fossils are much older than their closest competitors.

“The microfossils we discovered are about 300 million years older than the previously thought oldest microfossils,” Dominic Papineau, a lecturer at University College London and the study’s lead researcher, said in a video announcing the find. “So there are within a few hundred million years from the accretion of the solar system.”

In the statement, Papineau described these tiny fossils— they’re less than a millimeter long— as “direct evidence of one of Earth’s oldest life forms.”

Planet Earth itself is believed to be 4.5 billion years old.

One of the most exciting ramifications of the find is that since it shows that life began on Earth so long ago, perhaps the same thing could have happened in other places in our solar system— like Mars.

“These discoveries demonstrate life developed on Earth at a time when Mars and Earth had liquid water at their surfaces, posing exciting questions for extra-terrestrial life,” Dodd said, in the statement. “Therefore, we expect to find evidence for past life on Mars 4,000 million years ago, or if not, Earth may have been a special exception.”

The discovery was reported in a study published online Wednesday in the journal Nature.

Yeast has been engineered to produce the main psychoactive compound in marijuana – tetrahydrocannabinol (THC). Responsible for the majority of marijuana’s psychological effects – including the high – THC can also be use to treat symptoms of HIV infection and chemotherapy and researchers are hoping their yeast will be able to pump it out more efficiently than producing synthetic versions.

“This is something that could literally change the lives of millions of people,” Kevin Chen from Hyasynth Bio, a Canada-based company that’s been engineering yeasts to produce both THC and cannabidiol – another active compound that has shown promise as a medical treatment – told The New York Times.

Back in August, researchers from the University of California, Berkeley in the US announced that they’d figured out how to make ‘home-made’ heroin using a modified form of sugar-fed yeast and an enzyme extracted from poppies. They discovered that a certain type of enzyme can turn glucose sugars into morphine, and were able to successfully express it in a simple form of genetically engineered yeast.

Now, researchers from the Technical University of Dortmund in Germany have outlined in the journal Biotechnology Letters how they looked into which genes the marijuana plant uses to produce THC, and then engineered those genes into their yeast. They then fed a cocktail of specially chosen molecules to the yeast, and it essentially ‘poops’ out the THC.

They’ve also reportedly managed to produce cannabidiol in the same way, but are yet to publish the details. The big challenge now will be figuring out how to replace these molecules with a raw material such as sugar to make the process cheap, easy, and commercially competitive.

The purpose isn’t to replace the marijuana plant, because let’s face it, it’s doing a pretty good job on its own. As Jonathan Page, an adjunct professor at the University of British Columbia in Canada who helped sequence the THC and cannabidiol genes, told Roxanne Khamsi at The New York Times: “Right now, we have a plant that is essentially the Ferrari of the plant world when it comes to producing the chemical of interest. Cannabis is hard to beat.”

The idea instead is to offer up an alternative for places such as Europe, where medicinal compounds from marijuana would be welcomed if they didn’t come in the form of a plant that could be illegally farmed. And synthetic versions of THC are currently available in pill form to treat several side effects of having HIV or chemotherapy, but the chemical synthesis involved is complicated and expensive.

What yeast could also offer is the potential to more efficiently test the medicinal properties of specific active compounds in marijuana, which have shown promise in treating everything from seizures and inflammation to cancer and parkinson’s disease. Yasmin Hurd, a professor of neuroscience and psychiatry at Icahn School of Medicine at Mount Sinai, told Tech Insider that using all the compounds in marijuana simultaneously is like “throwing 400 tablets in a cocktail and saying ‘take this,'” rather than figuring out which component of that cocktail is really beneficial for the specific disease.

Because right now, rigorous scientific evidence showing that marijuana and its constituents effectively treat the symptoms of many of the illnesses for which they’ve been prescribed is lacking.

“Marijuana is increasingly embraced as medicine, yet there is limited evidencethat it is effective against many of the conditions for which it is prescribed,” The New York Times reports. “Researchers hoping to separate fact from wishful thinking will need much better access to marijuana’s unique constituents. Modified yeast may provide them.”

Physics may have just taken a new leap forward, as three independent groups of physicists have found strong evidence for massless particles called “Weyl fermions,” which exist as quasiparticles – collective excitations of electrons. Ultimately, this discovery is over 80 years in the making, dating back to Paul Dirac.

In 1928, Dirac came up with an equation that described the spin of fermions (fermions are the building blocks that make up all matter). Within his equation, he discovered that, in relation to particles that have charge and mass, there should be a another particle and antiparticle—what we know as the electron and (its antiparticle) the positron.

Yet, there are more than one ways to skin a cat.

Other solutions to this equation hinted at more exotic kinds of particles. Enter Hermann Weyl, a German mathematician who, in 1929, come up with a solution that involved massless particles. These became known as “Weyl fermions.” And, for a number of years, physicists believed that neutrinos (subatomic particles that are produced by the decay of radioactive elements) were actually Weyl particles. Yet, further studies, which were published in 1998, indicated that neutrinos do, in fact, have mass, which means that they cannot be the aforementioned Weyl particles.

But now, we have evidence that Weyl fermions actually exist.

Unlocking the Find

The research comes thanks to Zahid Hasan over at Princeton University, who uncovered these particles in the semimetal tanatalum arsenide (which is referred to as TaAs). Hasan and his team suggested that TaAs should contain Weyl fermions and (here is the important bit) it should have what is known as a “Fermi arc.” And in 2014, the team found evidence of such an arc.

But that’s not all, another team, led by Hongming Weng at the Chinese Academy of Sciences, found similar evidence in an independent study that used the same methods. And Marin Soljačić and colleagues (hailing from MIT and the Univeristy of China) have seen evidence of Weyl fermions in a different material, specifically, a “double-gyroid” photonic crystal.

In this latter case, the team fired microwaves at the crystal and measured microwave transmission through it, varying the frequency of the microwaves throughout the experiment. Through this process, the team could map the structure of the crystal, allowing them to determine which microwave frequencies can travel through the crystal and which cannot. In the end, this revealed the presence of “Weyl points” in the structure, which is strong evidence for Weyl fermion states existing within the photonic crystal.

The Future of Physics

The significance of this find, quite literally, cannot be overstated. Hasan is clear to point this out, noting in the press release that, “The physics of the Weyl fermion are so strange, there could be many things that arise from this particle that we’re just not capable of imagining now.”

He goes on to note more specific applications: “It’s like they have their own GPS and steer themselves without scattering. They will move and move only in one direction since they are either right-handed or left-handed and never come to an end because they just tunnel through. These are very fast electrons that behave like unidirectional light beams and can be used for new types of quantum computing.” Soljačić, the head of the second study, adds that, “The discovery of Weyl points is not only the smoking gun to a scientific mystery, it paves the way to absolutely new photonic phenomena and applications.”

Ultimately, it is believed Weyl fermions could be very useful, in that, because they are massless, they can conduct electric charge much faster than normal electrons. Admittedly, this same feature is exhibited by electrons in graphene. Yet, graphene is a 2D material, Weyl fermions are thought to exist in more practical 3D materials.

photo credit: Scientists are searching for collisions between different ‘universe bubbles’ in the cosmic microwave background. Geralt

The existence of parallel universes may seem like something cooked up by science fiction writers, with little relevance to modern theoretical physics. But the idea that we live in a “multiverse” made up of an infinite number of parallel universes has long been considered a scientific possibility – although it is still a matter of vigorous debate among physicists. The race is now on to find a way to test the theory, including searching the sky for signs of collisions with other universes.

It is important to keep in mind that the multiverse view is not actually a theory, it is rather a consequence of our current understanding of theoretical physics. This distinction is crucial. We have not waved our hands and said: “Let there be a multiverse”. Instead the idea that the universe is perhaps one of infinitely many is derived from current theories like quantum mechanics and string theory.

The Many-Worlds Interpretation

You may have heard the thought experiment of Schrödinger’s cat, a spooky animal who lives in a closed box. The act of opening the box allows us to follow one of the possible future histories of our cat, including one in which it is both dead and alive. The reason this seems so impossible is simply because our human intuition is not familiar with it.

But it is entirely possible according to the strange rules of quantum mechanics. The reason that this can happen is that the space of possibilities in quantum mechanics is huge. Mathematically, a quantum mechanical state is a sum (or superposition) of all possible states. In the case of the Schrödinger’s cat, the cat is the superposition of “dead” and “alive” states.

But how do we interpret this to make any practical sense at all? One popular way is to think of all these possibilities as book-keeping devices so that the only “objectively true” cat state is the one we observe. However, one can just as well choose to accept that all these possibilities are true, and that they exist in different universes of a multiverse.

String theory is one of our most, if not the most promising avenue to be able to unify quantum mechanics and gravity. This is notoriously hard because gravitational force is so difficult to describe on small scales like those of atoms and subatomic particles – which is the science of quantum mechanics. But string theory, which states that all fundamental particles are made up of one-dimensional strings, can describe all known forces of nature at once: gravity, electromagnetism and the nuclear forces.

However, for string theory to work mathematically, it requires at least ten physical dimensions. Since we can only observe four dimensions: height, width, depth (all spatial) and time (temporal), the extra dimensions of string theory must therefore be hidden somehow if it is to be correct. To be able to use the theory to explain the physical phenomena we see, these extra dimensions have to be “compactified” by being curled up in such a way that they are too small to be seen. Perhaps for each point in our large four dimensions, there exists six extra indistinguishable directions?

A problem, or some would say, a feature, of string theory is that there are many ways of doing this compactification –10500 possibilities is one number usually touted about. Each of these compactifications will result in a universe with different physical laws – such as different masses of electrons and different constants of gravity. However there are also vigorous objections to the methodology of compactification, so the issue is not quite settled.

But given this, the obvious question is: which of these landscape of possibilities do we live in? String theory itself does not provide a mechanism to predict that, which makes it useless as we can’t test it. But fortunately, an idea from our study of early universe cosmology has turned this bug into a feature.

While the exact details of the theory are still being hotly debated, inflation is widely accepted by physicists. However, a consequence of this theory is that there must be other parts of the universe that are still accelerating. However, due to the quantum fluctuations of space-time, some parts of the universe never actually reach the end state of inflation. This means that the universe is, at least according to our current understanding, eternally inflating. Some parts can therefore end up becoming other universes, which could become other universes etc. This mechanism generates a infinite number of universes.

By combining this scenario with string theory, there is a possibility that each of these universes possesses a different compactification of the extra dimensions and hence has different physical laws.

The universes predicted by string theory and inflation live in the same physical space (unlike the many universes of quantum mechanics which live in a mathematical space), they can overlap or collide. Indeed, they inevitably must collide, leaving possible signatures in the cosmic sky which we can try to search for.

The exact details of the signatures depends intimately on the models – ranging from cold or hot spots in the cosmic microwave background to anomalous voids in the distribution of galaxies. Nevertheless, since collisions with other universes must occur in a particular direction, a general expectation is that any signatures will break the uniformity of our observable universe.

These signatures are actively being pursued by scientists. Some are looking for it directly through imprints in the cosmic microwave background, the afterglow of the Big Bang. However, no such signatures are yet to be seen. Others are looking for indirect support such as gravitational waves, which are ripples in space-time as massive objects pass through. Such waves could directly prove the existence of inflation, which ultimately strengthens the support for the multiverse theory.

Whether we will ever be able to prove their existence is hard to predict. But given the massive implications of such a finding it should definitely be worth the search.

Good news for everyone with blurry vision or a strong desire to become Superman. The Ocumetics Bionic Lens may give you 60/20 eyesight — three times better than 20/20. It’s a major leap in eye prosthetics, and apparently, it’s pretty painless too.

Garth Webb, a British Columbia optometrist, founder of Ocumetics and the creator of the Bionic Lens, told CBC his product would allow someone who can’t make out an object at 10 feet to see it clearly from 30 feet. He also claims his surgically implanted lenses can prevent cataracts from forming because they replace the rotted human lens.

“At age 45 I had to struggle with reading glasses, which like most people, I found was a great insult,” Webb told CBC. “To this day I curse my progressive glasses. I also wear contact lenses, which I also curse just about every day.”

Webb says the surgery is identical to cataract surgery. The original lens you’re born with is removed, and then instead of replacing it with the usual artificial lens, the surgeon folds up Ocumetics’ Bionic Lens in a syringe and injects it into place. According to Webb, it’s an eight-minute surgery that leaves the patient with unprecedented eyesight — and could once and for all do away with contact lenses and glasses.

The Ocumetics Bionic Lens could do away with corrective lenses.Source: Getty Images

Ophthalmologist Vincent DeLuise, who teaches at Weill Cornell Medical College in New York, says this might be the real deal.

“There’s a lot of excitement about the Bionic Lens from very experienced surgeons who perhaps had some cynicism about this because they’ve seen things not work in the past,” DeLuise told CBC. “They think that this might actually work and they’re eager enough that they all wish to be on the medical advisory board to help him on his journey.”

Clinical trials on humans still need to be undergone. But the Bionic Lens isn’t a pipe dream with a far-off release date. If trials go smoothly, Webb says, the lens could start selling in Canada in two years, and elsewhere once individual governments sort out how to regulate it.

What’s so exciting is how many companies are taking a real swing at improving eyesight, from solar-powered sight to Wi-Fi-connected eyeballs. Webb and his team have allegedly invested over $3 million in researching the Bionic Lens. And if it’s successful, not only will it restore sight to those who’ve lost it, but it could spur a rise in recreational surgeries — and a whole lot of aspiring superheroes who can see ridiculously far.

Annalee Newitz

Today a group of paleontologists announced the results of an extensive study of several well-preserved dinosaur feathers encased in amber. Their work, which included samples from many stages in the evolution of feathers, bolstered the findings of other scientists who’ve suggested that dinosaurs (winged and otherwise) had multicolored and transparent feathers of the sort you might see on birds today. The researchers also presented evidence, based on the feathers’ pigmentation and structures, that today’s bird feathers could have evolved from dinosaur feathers.

These specimens represent distinct stages of feather evolution, from early-stage, single filament protofeathers to much more complex structures associated with modern diving birds . . . They can’t determine which feathers belonged to birds or dinosaurs yet, but they did observe filament structures that are similar to those seen in other non-avian dinosaur fossils.

Villarica also did io9 readers a favor and asked McKellar whether this discovery could lead to aJurassic Park scenario. McKellar said:

Put simply, no. The specimens that we examined are extremely small and would not be expected to contain any DNA material. To put this into context, the only genetic material that has been recovered from amber is from lumps of mummified insect muscle tissue in much younger Dominican amber that are approximately 17 million years old and well after the age of dinosaurs.

So much for our dreams of dino domination.

What you’ll notice in the gallery below is that the researchers are emphasizing two basic pieces of evidence: the similarity in coloration to today’s bird feathers, and the similarity in morphology or shape. Some of these feathers strongly resemble those of diving water birds today (and the researchers include one example of a modern diving bird feather so you can compare them). Other structures, however, look nothing like feathers of today. In a news report about McKellar’s findings in Science, Sid Perkins writes:

In one instance, the amber holds regularly spaced, hollow filaments, each of which is about 16 micrometers in diameter, about the size of the finest human hair. The filaments apparently have no cell walls, so they’re not plant fibers or fungal threads, McKellar says. And they don’t have features that look like small scales, as mammal hair does. “We don’t absolutely know what they are, but we’re pretty sure what they’re not,” he notes. They could be protofeathers, McKellar says.

Often this kind of structure is called “dinofuzz.”

Check out the feathers and the fuzz for yourself. All captions are taken from materials provided by the researchers in their paper, published today in Science.

An isolated barb from a vaned feather, trapped within a tangled mass of spider’s web in Late Cretaceous Canadian amber. Pigment distribution within this feather fragment suggests that the barb may have been gray or black. Image via Science/AAAS

Numerous individual filaments in Late Cretaceous Canadian amber. These filaments are morphologically similar to the protofeathers that have been found as compression fossils associated with some dinosaur skeletons. Pigment distributions within these filaments range from translucent (unpigmented) to near-black (heavily pigmented). Image via Science/AAAS

Cross-section through a feather with basally-coiled barbules, accompanied by a microphysid plant bug. The helical coiling observed within these barbules is most obvious in isolated barbules within the image, and is directly comparable to coils found in modern bird feathers specialized for water uptake. The high number of coils in the amber-entombed feather is suggestive of diving behavior, but similar structures are also used by some modern birds to transport water to the nest. Image via Science/AAAS

Series of six feather barbs in Late Cretaceous Canadian amber. Localized pigmentation creates a beaded appearance within each barbule: This has implications for the structural interpretation of fossil feathers exhibiting this general morphology. Pigment distribution within the specimen suggests that the feather would have originally been medium- or dark-brown in color. Image via Science/AAAS

Photomicrograph of coiled barbules in Late Cretaceous Canadian amber. The cork-screw shaped structures in the image are the tightly coiled bases of feather barbules, and these are interrupted towards the bottom of the image, where they exit the amber piece. Image via Science/AAAS

An isolated barb from a white belly feather of a modern grebe bird (Aechmophorus occidentalis), illustrating coiled barbule bases comparable to those in the Cretaceous specimen. In both cases, the coiling is a structural adaptation that allows the feather to absorb water.Image via Science/AAAS

A feather barb within Late Cretaceous Canadian amber that shows some indication of original coloration. The oblong brown masses within the dark-field photomicrograph are concentrated regions of pigmentation within the barbules. In this specimen, the overall feather color appears to have been medium- or dark-brown. Image via Science/AAAS

Science notes that Europe is often thought of as the “ancestral home of white people.” But a new DNA study suggests that pale skin and other traits we associate with the continent may have emerged only within the last 8,000 years—a “relatively recent” occurrence.

The study—published last month on the bioRxiv.com server and presented last week at the American Association of Physical Anthropologists’ annual meeting—compared genome DNA across three populations of farmers and hunter-gatherers who crossed over into Europe in discrete migrations within the past eight millennia, Science notes.

What scientists found: a handful of genes tied to diet and skin pigmentation that withstood natural selection and thrived in the northern regions. The data indicates hunter-gatherers who settled in Spain, Hungary, and Luxembourg about 8,500 years ago lacked two specific genes—SLC24A5 and SLC45A2—and had darker skin, Science notes.

But hunter-gatherers hunkered down further north in Sweden had both those light-skin genes and also a third gene that leads to blue eyes (and possibly fair skin and blond hair).

When the third demographic, the Near East farmers, arrived, they also carried the SLC24A5 and SLC45A2 genes, so paler skin started emerging throughout the continent as the populations interbred.

Although researchers don’t offer a definitive answer as to why natural selection picked those genes to thrive in the north, one paleoanthropologist speculated at the meeting that the lack of sun in the northern parts of Europe required people to adapt by developing lighter skin to better absorb more vitamin D, as well as the LCT gene that allowed them to digest the sugars their ancestors couldn’t in milk, also filled with vitamin D.